Figure 6.
Effects on Developmental Timing Are Likely due to Disruption in PTTH and Ecdysone Levels
(A) As development proceeds, prothoracicotropic hormone (PTTH) is produced in the brain of the larva and released in the prothoracic gland (PG), where it induces the expression of the genes of the molting hormone ecdysone synthesis pathway.
(B and B′) Transcription levels of spookier (B) and neverland (B′) (expressed in copy number) at different time points in third-instar larvae (L3), synchronized at second- to third-instar molt, upon downregulation of sbm in glia (Repo-Gal4) (two-way ANOVA with a Duncan post-test; data were transformed to ln to fulfill the test criteria, p < 0.05, F = 3.12 and F = 3.93; n = 5).
(C) Photograph depicting the difference in relative sized between the RG and brain in 102 hAEL larvae (equivalent to ∼37 hours after L2–L3 molt) and RG area measurements expressed in 103 μm2 (t test t = 0.40; n.s., nonsignificant differences; n = 11).
(D and D′) Somatic PTTH (D) and neuronal somatic Sbm levels (D′; as internal control) at different time points in synchronized third-instar larvae upon downregulation of sbm in glia (Repo-Gal4). In both cases, one-way ANOVA with a Duncan post-test was used. In (D), p < 0.05, F = 14.46, n = 40–46. In (D′), p = 0.71, F = 3.37, n = 40–46.
(D″) Representative images of somatic PTTH (green) levels and Sbm (magenta) levels in the sbm-expressing neurons.
In all graphs, data represent mean ± SEM, and different letters signify groups that are significantly different (p < 0.05) in a Duncan post-test.